Thermo-magnetic refrigerant valve



19, 1957 EL ROY J. KRAFT THERMO-MAGNETIC REFRIYGERANT VALVE Filed July13. 1955 CONDENSER COMP/F5155 0R .EIL/"EIZUT Unite tates PatentTHERMO-MAGNETIC REFRIGERANT VALVE El Roy J. Kraft, Des Plaines, 111.,assignor to The Dole Valve Company, Chicago, Ill., a corporation ofIllinois Application July 13, 1955, Serial No. 521,749

" 6 Claims. (Cl. 236-48) the temperature of the high temperaturerefrigerating compartment.

.Another object of the invention is to provide a new and improved formof thermo-magnetic valve particularly adapted to control the temperatureof the high temperature compartment of a dual temperature-refrigeratingsystem.

' A further object of the invention is to providea refrigerant controlvalve in which a thermal element is located in a position subject to thetemperature of a compa'rtment being cooled and controls the flow ofrefrigerant through the compartment in accordance with the temperaturethereof.

A further object of the invention is to provide a valve for controllingthe'flow of refrigerant through the evaporator of a refrigerant line toeffect a uniform temperature in the compartment being refrigerated, andoperated by a power type of thermal element having an extensible pistonmoving a magnetic field in position to envelope the valve and effectopening thereof.

Another and more detailed object of the invention is to provide arefrigerant control valve for the secondary refrigerant loop of a dualtemperature refrigerating system in which the valve is in the form of anarmature actuated to an open position by a magnet biased in a directionto permit closing of the valve, and moved in a direction to envelope thevalve with its magnetic field by the extensible plunger of a power typethermal element adapted to be positioned in the flow of air through thesecondary refrigerating compartment of the refrigerating system.

These and other objects of the invention will appear from time to timeas the following specification proceeds and with reference to theaccompanying drawing wherein:

Figure l is a circuit diagram of a dual temperature refrigerating systemdiagrammatically showing a thermostatically operatedcontrol valve in thesecondary refrigerant line for the high temperature refrigeratingcompartment; and

Figure 2 is a longitudinal sectional view taken through athermo-magnetic refrigerant valve constructed in accordance with myinvention.

In Figure l of the drawing, I have shown a typical dual temperaturerefrigerating system of the thermal syphon type in which a motor drivencompressor 10 serves to compress a suitable refrigerant, such as Freonor a like gas and supply the same to a condenser 11 through a pressureline 12. From the condenser, the refrigerant condensed to a liquid maypass through a 2,781,979 Patented Feb. 19, 19 57 ice capillary tube 13to and through an evaporator or cooling coil 15 where heat is absorbed.The refrigerant then passes through a return line 16 back to thecompressor, as is usual in closed circuit refrigerating system used fordomestic purposes.

The evaporator 15 is in association with a low ternperaturerefrigerating compartment 17, for maintaining said compartment at adesired, low temperature, as for example, 10 below zero F.

A secondary refrigerant loop 20 is shown as being in heat exchangerelation with respect to the evaporator 15 and has an evaporator 21associated therewith which may be located in a secondary refrigeratingcompartment 22 of the refrigerator for maintaining said compartment at ahigher temperature than the temperature of the compartment 17, as forexample 40 F.

Located in the secondary refrigerating compartment 22 and connected in arefrigerant line 18 leading to the evaporator 21 is a control valve 23for controlling the flow of refrigerant through the secondaryrefrigerant loop in accordance with the need for refrigeration in thesecondary refrigerating compartment 22.

The control valve 23 as shown in Figure 2 includes a valve body 24having an inlet 25 leading into a chamber 26 in said valve body andhaving a reduced diameter port 27 leading to an outlet 28. The port 27is shown as being engaged by a valve 29 on the lower end of an armature30, and formed integrally therewith.

The armature 30 is shown as being slidably' guided in the valve chamber26 and in a guide and closure mem ber 32, seated in the valve body 24and extending upwardly through a wall 33 of a housing 35 for a magneticactuator 36.

As herein shown, the armature 30 and valve 29 drop by gravity to closethe port 27 and block the flow of refrigerant through the secondaryrefrigerant loop 20, and move out of engagement with the port 27 uponthe envelopment of the armature 30 with the magnetic field of themagnetic actuator 36.

The magnetic actuator 36 is shown as comprisinga lever arm 37 pivotedwithin the housing 35 on a transverse pivot pin 39, which may be mountedin the walls of said housing. The lever arm 37 is shown as extendingover the guide and closure member 32 and as having a rectangular recessor receptacle 40 at its free end, carrying a magnet 41. I The magnet 41is herein shown as being a bar, rectangular incross-section and may bemade from Alnico, Permalloy or a steel having high remanence andcoercive force and containing high percentages of tungsten or cobalt.

The arm 37 has a portion 43, the inner margin of which defines the outermargin of the recess 40, which extends inwardly beyond the magnet 41 andhas an upwardly and inturned end 44, forming a hook, and shown as havinga tension spring 45 hooked thereto. The opposite end of the tensionspring 45 from the hook 44 is shown as being hooked to a U-bolt 46secured to and extending inwardly from a wall 47 of the casing 35. Thespring 45 thus biases the lever 37 and magnet 41 in the upright positionshown in Figure 2 with the magnetic field of the magnet out ofenveloping relation with the armature 30.

The magnet 41 ismoved against the bias of the spring 45 into envelopingrelation with respect to the armature 30 by means of a piston 49 of athermal element 50. The thermal element 50 is shown as having a cylinder51 threaded within the wall 47 and positioning the piston 49 to engage'ashoulder 53 of the lever 37, for pivoting said lever against the bias ofthe spring 45 toward the guide and closure member 32.

The thermal element 50 may be a socalled power type 3 of thermalelement, such as isshown and described in the Vernet Patent No.2,368,181, dated January 30, 1945, and frequently referred to as aVernay thermal element. In such types of thermal elements, a fusiblematerial (not shown) is carried in the casing 55 of the thermal elementand acts against a membrane or a deformable member (not shown), toextend the piston 49 from the cylinder 51 upon a suficient rise intemperature to effect fusion of the fusible material. The fusiblematerial is selected for its temperature of fusion and may be of variousforms and materials. The casing 55 isencircled by a metal ring 56, whichmay be suitably secured thereto and forms a heat conductor for saidcasing.

A sleeve 57 is shown as encircling the casing SS and as being securedthereto for turning the same upon turning movement of said sleeve. Thesleeve 57 is shown as having spaced radiating fins SQeXtendingthereabout, and as extending through an opening 69 formed in a wall 61spaced outwardly from the wall 47 and secured to the wall 47 as by aside wall 63. A knob 64 is shown as being secured to the sleeve 57 forturning the same. The knob 64 has an indicator or pointer 65 extendingtherefrom which may cooperate with indicia (not shown), which may be onthe outer face of the wall 61, to indicate the temperature setting ofthethermal element.

The temperature at which the, thermal element 50 moves the lever arm 37-and magnet 41 in position to effect opening of the valve 29, may bevaried by varying the travel of the, piston 49 necessary to move thelever 37 and magnet 41 from the upwardly extending position shown inFigure 2 to the downwardly extended broken line position shown in thisfigure. This, is attained by turning of the entire thermal element withrespect to the, wall 47 and varying the position of the cylinder withrespect to the shoulder 53.

The housing 35 may be located in the secondary refrigerating compartmentin such a position as to, place the thermal element 50 in the path ofcold air circulated through the high temperature chamber, commonlycalled the 40 chamber. When the temperature of the secondaryrefrigerating compartment is above the temperature setting of thethermal element 50, the piston 49 will move outwardly along the cylinder51, pivoting the lever arm 36, downwardly toward the cap. 32 and movingthe magnet 41 against the top of said cap. The armature 30 will then beenveloped in the magnetic field of the magnet and will rise to the topof the guide and closure member 32, opening the valve 29 and permittingthe circulation of refrigerant from the inlet 25 out through the outlet28 and through the secondary refrigerantloop.

As the temperature in the secondary refrigerating compartment becomescolder, the piston 49 will 'be retractibly moved within the cylinder 51by the spring 45. The spring 45 will also move the magnet 41 away fromthe armature 30 until the magnetic, field becomes so weak that thearmature 30 will drop to engage the valve 29 with the port 27 and blockthe flow of refrigerant through the secondary refrigerant loop.

While I have herein shown and described one form in which my inventionmay be embodied, it should be understood that I do not wish to belimited to the specific form shown, but that various modifications andvariations of the invention may be effected without departing from thespirit and scope of the novel concepts thereof.

I claim as my invention:

1. In a refrigerant shut-off valve particularly adapted to shut-ofi theflow of refrigerant in a secondary refrigerant loop of a dualtemperature refrigerator, a valve body having a central valve chamber,an inlet leading into said chamber and an outlet leading therefrom, ametallic valve biased "by gravity to block the passage of refrigerantfrom said inlet to said outlet, a housing extending from said valve bodyand having said valve movable therein, an arm pivotally mounted in saidcasing for movement toward and from said valve, at least an outerportion of which is magnetic, a thermal element having a cylinderextending within said housing, a casing on the outside of said housingand a piston extensible from said cylinder into engagement with said armupon predetermined rises in temperature, for moving said arm toward saidvalve to envelope said valve with the magnetic field of said arm andeffect opening thereof, and a spring having connection with said arm forbiasing said magnet away from said; valve to accommodate said valve toclose by gravity, and for retractibly moving said piston within saidcylinder.

2. in a valve particularly adapted to control the fiow of refrigerantin; a secondary refrigerant loop of a dual temperature refrigerator, avalve body having a chamber therein, an inlet leading into said chamberand an outlet leading therefrom, a housing associated with said valvebody, an armature guided for movement along said valve body and having avalve on the lower end thereof for blocking the flow of fluid from saidinlet through said outlet, an arm pivoted within said housing formovement toward' and from said valve, a permanent magnet on the free endof said arm and moved thereby to envelope said armature with itsmagnetic field, a thermal element having a cylinder threaded within awall of said housing and a piston extensible from said cylinder andhaving engagement with said arm for pivoting the same toward saidarmature upon extensible movement thereof with respect to said cylinder,and a spring biasing said arm and magnet away from said armature toweaken the magnetic field around said armature sufiiciently toaccommodate said valve to close by gravity and retractibly moving saidpiston within said cylinder.

3. In a valve particularly adapted to control the flow of' refrigerantin a secondary refrigerant loop of a dual temperature refrigerator, avalve body having a chamber therein, an inlet leading into said chamberand an outlet leading therefrom, a housing in association with saidvalvebody, an armature guided for movement along said valve body withinsaid housing and having a valve on the lower end thereof for blockingthe flow of fluid from said inlet through said outlet, an arm pivotedwithin said housing from movement toward and from said valve, apermanent magnet on the free end of said arm and moved thereby toenvelope said armature with its magnetic field to effect opening of saidvalve, a thermal element having a cylinder threaded within a wall ofsaid housing, a piston extensible, from said cylinder upon predeterminedincreases in temperature and having engagement with said arm forpivoting the same toward said armature upon, extensible movement thereofwith respect to said cylinder, a spring biasing said arm and magnet awayfrom said armature to weaken the magnetic field sufiiciently toaccommodate said valve to close by gravity and also retractibly movingsaid piston within said cylinder upon predetermined reductions intemperature, and a knob having operative connection with said thermalelement for turning the same to vary the position of said piston withrespect to said arm and the temperature of operation of said thermalelement to move said arm and magnet in position to envelope saidarmature with its magnetic field.

4. In a thermally operated refrigerant shut off valve, a valve bodyhaving an inlet and an outlet and a central valve chamber, a portbetween said inlet and outlet, an armature slidably guided withinsaidvalve chamber and having a valve on the end thereof engageable with saidport, an arm pivoted for movement toward and from said armature, apermanent magnet on the free end of said arm, a spring biasing saidmagnet away from said armature, and a thermal element having a casing onthe outside of said valve body and having a piston extensible withrespect to said casing upon predetermined increases in temperature, anda shoulder on said arm engaged by said piston upon extensible movementthereof with re spect to said cylinder.

' 5. A shut-off valve comprising a valve body having an inlet and anoutlet and a central valve chamber, a housing associated with said valvebody, an armature guided within said valve chamber and having a valve onthe end thereof, a guide and a closure for said armature, extendingwithin said housing and sealing said valve chamber therefrom, an armpivoted within said housing for movement toward and from said guide andclosure member, a permanent magnet on the free end of said arm, a springbiasing said arm and magnet away from said guide and closure member, anda thermal element having a casing on the outside of said housing, ,acylinder extending within said housing and a piston extensible from saidcylinder upon predetermined increases in temperature, and a shoulder onsaid arm facing said piston and engaged thereby upon extensible movementthereof with respect to said cylinder.

6. A shut-off valve comprising a valve body having an inlet and anoutlet and a central valve chamber, a housing associated with said valvebody, an armature guided within said valve chamber and having a valve onthe end thereof, a guide and closure for said armature extending withinsaid housing and sealing said valve chamber therefrom, an arm pivotedwithin said housing for movement toward and from said guide and closure,a permanent magnet on the free end of said arm, a spring biasing saidarm and magnet away from said guide and closure, a thermal elementhaving a casing on the outside of said housing, a cylinder extendingwithin said housing and a piston extensible from said casing uponpredetermined increases in temperature, said arm having a shoulderfacing said piston and engaged thereby upon extensible movement thereofwith respect to said cylinder, and means for adjustably moving saidcylinder with respect to said shoulder to vary the temperature necessaryto operate said arm to bring said permanent magnet into position toefiect opening of said valve.

References Cited in the file of this patent UNITED STATES PATENTS1,837,871 Kindermann Dec. 22, 1931 2,044,609 Hedlund June 16, 19362,368,181 Vernet Jan. 30, 1945 2,405,127 Beach Aug. 6, 1946 2,657,861Dillman Nov. 3, 1953

